Technical Field
The present disclosure relates to an imaging device and an imaging system.
Description of the Related Art
Imaging devices capable of performing both focus detection and image capturing have been proposed. According to Japanese Patent Laid-Open No. 2013-106194, each pixel of an imaging device includes a first photoelectric conversion portion and a second photoelectric conversion portion. The first and second photoelectric conversion portions are each disposed to be substantially conjugate to the pupil of the lens. During focus detection, signals are read out independently from the first and second photoelectric conversion portions of a plurality of pixels, and two images are formed based on rays that have passed through different positions of the pupil of the lens. An image of a subject can be obtained (captured) by adding the signals from the first and second photoelectric conversion portions together.
Japanese Patent Laid-Open No. 2013-106194 also discloses an imaging device that includes a common amplifier for each pair of the first photoelectric conversion portion and the second photoelectric conversion portion. Specifically, a configuration of such an imaging device for outputting a signal based on a charge in the first photoelectric conversion portion and an added signal obtained by adding charges in the first and second photoelectric conversion portions is disclosed.